Ultrafast and Facile Synthesis of (Ni/Fe/Mo)OOH on Ni Foam for Oxygen Evolution Reaction in Seawater Electrolysis

Abstract

Preparing high-performance electrocatalysts for oxygen evolution reaction (OER)s with high durability for seawater electrolysis is of great significance. Herein, reported a one-step solution-immersion synthesis strategy to prepare a (Ni/Fe/Mo)OOH catalyst on a nickel foam substrate that can be accomplished in 5 min under ambient temperature and pressure. The unique cluster morphology of the catalyst on the surface of electrodes effectively increases the number of active sites, and the presence of Mo, Ni, and Fe in the catalyst enhances the activity of the OER. In the electrolyte solution (1 mol/L NaOH), the electrode exhibited low OER overpotentials of 265 mV, 286 mV, and 332 mV at currents of 100 mA·cm−2, 400 mA·cm−2, and 1000 mA·cm−2, respectively. This electrode also demonstrated excellent performance in seawater splitting, and the overpotentials at currents of 100 mA·cm−2, 400 mA·cm−2, and 1000 mA·cm−2 in alkaline seawater environments were 330 mV, 416 mV, and 514 mV, respectively. In the 72 h durability test, the voltage increase was within 10 mV, exhibiting the excellent durability of the (Ni/Fe/Mo)OOH electrocatalyst. Therefore, the electrode developed here shows potential in the application of seawater electrolysis for hydrogen generation.